The question was inspired by this thread about butt hair. It’s true, in museums and artistic renderings of cave men, they’re always hairier than modern man, even correcting for the lack of razors and scissors. Sometimes even the women have furry arms. How do we know this? Can hairiness somehow be detected in ancient remains? Have we seen cave paintings of hairy people? Or are we just assuming that since we have a common ancestor with hairy gorillas, that we must have been hairier at some time in the past?
I think it is virtually certain to be this (or, at least, that the tradition started out with someone thinking this way).
Of course, we now know that we are more closely related to chimps than to gorillas, but they are hairy too.
We don’t.
No.
No. Depictions of humans in paleo art are almost always just stick figures.
Basically, this. We know that our closest living relatives, chimps, have more well developed hair than we do. We assume that our common ancestor was also hairy. Since our relative hairlessness is probably an adaptation to shedding heat in pursuit hunting in savannas, it probably arose at some point after we split off from chimps. But at what point after that we reached our present relative hairlessness is unknown, although it would have been before humans left Africa while we still lived in tropical climates.
Right, but primitive homo sapiens, who are identical to us genetically, are also depicted as hairier. I think this is just a matter of “artistic license”, AKA bullshit.
Yes. This is the necessary conclusion for believers in evolution. There’s no reason that body hair would disappear all at once during speciation. It would be a gradual process as we evolved, and it’s not unfair to assume it would be linear.
As far as whether homo sapiens were actually as hairy as their museum statues indicate, or how hairy they were, I don’t know. I assume that anthropologists aren’t just pulling it out of their (hairy!) asses, though. My (educated?) guess is simple interpolation. If we know at what point our species diverged from a common ancestor, and we know how hairy that species is now, and how hairy we are now, then we can at least make an educated guess as to how hairy we were at certain points along the way.
There is no reason to suppose that Cro-Magnons were any hairier than modern Europeans. For that matter, there is no reason to suppose that Neanderthals were either.
It’s pretty much an educated guess, with the accent on “educated.” There are valid reasons to believe we used to be hairy, while lacking in direct evidence.
Probably not. Selection and hence evolutionary change tends to take place more easily in small, isolated populations. Big changes may take rapidly, and selection may become less intense once the population expands. Evolutionary change is probably rarely linear.
Is it plausible that fossils might eventually be found that preserved the hair? We have fossils showing feathers or proto-feathers, right?
On a semi-related note, on a museum tour about dinosaurs, I was told that we really don’t know what color the various species of dinosaurs really were. They could have been green, purple, striped, etc.
Whenever you see a re-construction of a dinosaur, they took a complete guess at the skin color.
We have frozen woolly mammoths with preserved hair, so it’s not impossible a Neanderthal could have been preserved in this manner somewhere. Also mummified ground sloths have been found in dry caves in which the hair has been preserved.
Fossil feather impressions have usually been found in very fine grained sediments. It’s unlikely that a human would be preserved in such a way as to give much information about the amount or distribution of body hair.
So? Sometimes modern women have furry arms, too.
I haven’t noticed a trend of restoring prehistoric Homo sapiens as exceptionally hairy (being a fairly hairy guy myself might have something to do with that).
OT, we like to call them cave men but i doubt if many of them liked to live in caves on a permanent basis.
According to Before the Dawn, it’s estimated that proto-humans lost most of their hair around 1.2 million years ago, based on tracking the mutation of a certain melanocortin receptor gene. Apparently the loss of hair triggered this, for skin protection from the sun.
The time period for when humans began styling their hair has also been estimated - 200,000 years ago. This is from tracking the mutation of a keratin gene, phi-hHaA, which is related to hair growth (page 26 of the book).
I’m not sure where you guys are seeing all these hairy H. sapiens. Most books or exhibits that I’ve seen in the last 25 years or so are careful to depict Cro Magnons (or early sapiens) as pretty much like us. Same with Neanderthals-- no extra hair. Usually you see H. *erectus * with slightly more hair and H. *habilis *pretty hairy.
Thanks. I was unaware of that research. I should have mentioned that it would be possible in principle to estimate the timing of hair loss if we knew more about the genetic basis for. (In this case the estimate is indirect, and not based on the genes for hair growth themselves.)
The original paper is Alan R. Rogers, David Iltis, and Stephen Wooding, “Genetic Variation at the MC1R Locus and the Time Since Loss of Human Body Hair”, Current Anthropology, 45:105-108 (2004).
Lots of fascinating inferences from genetics in the book (Before the Dawn), including estimates of when humans started wearing clothes. That’s based on lice genetics, and the estimate is 72,000 years ago.
Plus, it let me scoop Colibri on a biology-related question. Estimate of when that will happen again: 1.2 million years from now.
this might deserve a new thread but where is thick body/facial hair beneficial, very hot or very cold climate?
